1 //===--------- inline implementation of arm syscalls --------------* C++ *-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
10 #define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
11
12 #include "src/__support/common.h"
13 #include "src/__support/macros/config.h"
14
15 #ifdef __thumb__
16 #define R7 long r7 = number
17 #define SYSCALL_INSTR(input_constraint) \
18 int temp; \
19 LIBC_INLINE_ASM(R"(
20 mov %[temp], r7
21 mov r7, %2
22 svc #0
23 mov r7, %[temp]
24 )" \
25 : "=r"(r0), [temp] "=&r"(temp) \
26 : input_constraint \
27 : "memory", "cc")
28 #else
29 #define R7 register long r7 asm("r7") = number
30 #define SYSCALL_INSTR(input_constraint) \
31 LIBC_INLINE_ASM("svc 0" : "=r"(r0) : input_constraint : "memory", "cc")
32 #endif
33
34 #define REGISTER_DECL_0 \
35 R7; \
36 register long r0 __asm__("r0");
37 #define REGISTER_DECL_1 \
38 R7; \
39 register long r0 __asm__("r0") = arg1;
40 #define REGISTER_DECL_2 \
41 REGISTER_DECL_1 \
42 register long r1 __asm__("r1") = arg2;
43 #define REGISTER_DECL_3 \
44 REGISTER_DECL_2 \
45 register long r2 __asm__("r2") = arg3;
46 #define REGISTER_DECL_4 \
47 REGISTER_DECL_3 \
48 register long r3 __asm__("r3") = arg4;
49 #define REGISTER_DECL_5 \
50 REGISTER_DECL_4 \
51 register long r4 __asm__("r4") = arg5;
52 #define REGISTER_DECL_6 \
53 REGISTER_DECL_5 \
54 register long r5 __asm__("r5") = arg6;
55
56 #define REGISTER_CONSTRAINT_0 "r"(r7)
57 #define REGISTER_CONSTRAINT_1 REGISTER_CONSTRAINT_0, "r"(r0)
58 #define REGISTER_CONSTRAINT_2 REGISTER_CONSTRAINT_1, "r"(r1)
59 #define REGISTER_CONSTRAINT_3 REGISTER_CONSTRAINT_2, "r"(r2)
60 #define REGISTER_CONSTRAINT_4 REGISTER_CONSTRAINT_3, "r"(r3)
61 #define REGISTER_CONSTRAINT_5 REGISTER_CONSTRAINT_4, "r"(r4)
62 #define REGISTER_CONSTRAINT_6 REGISTER_CONSTRAINT_5, "r"(r5)
63
64 namespace LIBC_NAMESPACE_DECL {
65
syscall_impl(long number)66 LIBC_INLINE long syscall_impl(long number) {
67 REGISTER_DECL_0;
68 SYSCALL_INSTR(REGISTER_CONSTRAINT_0);
69 return r0;
70 }
71
syscall_impl(long number,long arg1)72 LIBC_INLINE long syscall_impl(long number, long arg1) {
73 REGISTER_DECL_1;
74 SYSCALL_INSTR(REGISTER_CONSTRAINT_1);
75 return r0;
76 }
77
syscall_impl(long number,long arg1,long arg2)78 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2) {
79 REGISTER_DECL_2;
80 SYSCALL_INSTR(REGISTER_CONSTRAINT_2);
81 return r0;
82 }
83
syscall_impl(long number,long arg1,long arg2,long arg3)84 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3) {
85 REGISTER_DECL_3;
86 SYSCALL_INSTR(REGISTER_CONSTRAINT_3);
87 return r0;
88 }
89
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4)90 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
91 long arg4) {
92 REGISTER_DECL_4;
93 SYSCALL_INSTR(REGISTER_CONSTRAINT_4);
94 return r0;
95 }
96
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4,long arg5)97 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
98 long arg4, long arg5) {
99 REGISTER_DECL_5;
100 SYSCALL_INSTR(REGISTER_CONSTRAINT_5);
101 return r0;
102 }
103
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4,long arg5,long arg6)104 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
105 long arg4, long arg5, long arg6) {
106 REGISTER_DECL_6;
107 SYSCALL_INSTR(REGISTER_CONSTRAINT_6);
108 return r0;
109 }
110
111 } // namespace LIBC_NAMESPACE_DECL
112
113 #undef REGISTER_DECL_0
114 #undef REGISTER_DECL_1
115 #undef REGISTER_DECL_2
116 #undef REGISTER_DECL_3
117 #undef REGISTER_DECL_4
118 #undef REGISTER_DECL_5
119 #undef REGISTER_DECL_6
120
121 #undef REGISTER_CONSTRAINT_0
122 #undef REGISTER_CONSTRAINT_1
123 #undef REGISTER_CONSTRAINT_2
124 #undef REGISTER_CONSTRAINT_3
125 #undef REGISTER_CONSTRAINT_4
126 #undef REGISTER_CONSTRAINT_5
127 #undef REGISTER_CONSTRAINT_6
128
129 #endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
130